This technote describes how to troubleshoot when you receive a black screen during a Control or Observe session.

Situation:

When controlling or observing a Windows Host machine, the screen remains black and never displays the Host desktop, however non-video sessions such as Exchange works without problems.

Solution:

Situation #1: Host machine may not be using a compatible build of Timbuktu.

Make sure you are using a compatible build of Timbuktu on the Host (controlled) machine. To check if you are using the latest compatible build of Timbuktu, go to http://www.netopia.com/support/wincompatibility.html. If the Host machine is running Windows XP with Timbuktu Pro 2000 builds 853 or below, then you must upgrade the version of Timbuktu on that machine. The remote control component in previous versions of Timbuktu does not support Windows XP.

Situation #2: Timbuktu may be having compatibility issues with the Host video card or driver or video settings.

If the Host machine is using a compatible build of Timbuktu and you have build 853 or higher,

1. Go to Setup > Preferences > Observe/Control tab.
2. Uncheck "Use accelerated remote control".
3. Click OK,
4. Go to the File menu and select Exit and Shutdown Timbuktu Pro.
5. Re-launch Timbuktu.

If you do not have build 853 or higher,

1. Check if the Host machine has the latest recommended video driver from the manufacturer of the video card on the Host machine.
2. Try lowering the colors and resolution on the Host.
3. Else upgrade to build 853 or above.

Situation #3: Video packets might be getting dropped or degraded due to packet size sent through a router or VPN connection.

If you are connecting over the internet from Windows 2000/XP through a cable/DSL router, make sure the MTU settings on the router on each end are set to 1492 or lower (if applicable). The default MTU settings on some routers are 1500, however data packets this size can sometimes be too large for some connections, causing the data to be degraded. If the router is set to 1492 or below and you are connecting to or from Windows XP, open the registry and go to

HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces

Create a new DWORD: MTU Value: 1492 (decimal)

Creating this new DWORD will overrides the default MTU for the network interface it is added to.